How Do Disease-Resistant Genetically Engineered Crops Make Humans (And Plants) More Vulnerable to Viruses?

By Jeffrey M. Smith

The US Department of Agriculture recently allowed the introduction of a new variety of plum, genetically modified (GM) to resist the plum pox virus. It hasn‘t yet been put into the food supply, but now the plum industry can do so if they choose.

Disease-resistant crops comprise less than one percent of the acreage devoted to GM varieties worldwide, but occupy a much bigger portion in biotech promotional literature. That‘s because engineering a crop to resist disease sounds more appealing than inserting a gene to make a crop produce its own pesticide or withstand herbicide -- the two traits that make up the other 99 percent of today‘s GM world.

There are three commercialized virus-resistant GM varieties in the food supply: zucchini, crookneck squash, and the only commercialized GM fruit, papaya. GM papaya grows solely in Hawaii and was introduced in 1998 to protect the crop from the devastating ring-spot virus. But according to a May 2006 report by Greenpeace, the GM papaya turned out to be "more devastating than the virus."

Upon introduction, the selling price for the papaya crashed from $1.23 per kilo to $0.89, after "traditional buyers of Hawaiian papayas, such as Japan and Canada, rejected [it]." Now, if Hawaiian papaya growers want to sell to Japan, they have to pay extra for segregating and testing their papayas to make sure they are non-GM. The Japanese market shrank from $10.3 million in 1998 to $4.6 million in 2005.

Although Canada started accepting GM papayas in 2003, the price didn‘t recover. In the 2004 and 2005 growing seasons, the selling price "averaged less than $0.80 per kilo, at or only marginally above production cost for many farmers."¹ While business is booming in other papaya growing regions, Hawaiian production is at its lowest point in more than a generation.

This didn‘t stop the USDA from trying to gift the plum industry with a virus-resistant catastrophe of its own... despite the fact that the plum pox virus is not even a current threat. According to Steve Poe, Senior Operations Officer who coordinates the USDA‘s program to wipe out the virus (using non-GM methods), "We‘re on the tail end of eradicating this thing." The incidence of the disease is down to about 1 tree per year, he says.

CLICK HERE to encourage the plum industry to reject the USDA plan of producing GM plums and prunes -- for the sake of our national health.

But the current threat that the USDA and other agencies continue to disregard is that virus-resistant crops-already on the market-may be increasing consumers‘ susceptibility to viral infections and, ironically, even putting the crops at greater risk.

According to virologist Jonathan Latham of the Bioscience Resource Project, "None of the important questions about the safety of viral transgenes have been answered. We still have no idea whether they will cause the evolution of new viruses by recombination, or what will be the effect of putting viral proteins into plants."

Gene Silencing and Virus-Protection

Although some viruses are DNA-based, most plant viruses exist as RNA strands. Normally, when an RNA virus attacks a cell, it copies itself in whopping numbers. The copies, in turn, produce viral protein, helping disable the cell‘s defenses to viruses.

Plants developed a gene silencing mechanism to defend against this onslaught. When the cell recognizes an RNA virus, the double stranded RNA (dsRNA) is cut into short pieces and stripped into a single strand. That strand is used as a reference to "find" other RNA with identical or similar sequences, which are then destroyed or degraded.

Each viral resistant GM crop is designed to protect against a specific RNA virus. Scientists first identify a piece of RNA from the "target" virus, and then build a piece of DNA-a transgene-with a sequence designed to create the viral RNA.

The transgene is inserted into the genome of a plant cell, which in turn grows into a plant. Every cell of that plant and its offspring has the inserted transgene "transcribed" into viral RNA. Thus, it arms the gene-silencing mechanism to be on the lookout for the target virus. The RNA may also produce viral proteins in every cell.

There are four components of a virus-resistant GM plant that must be considered when looking at the possible effects on humans, each of which carries unique risks:

• The viral protein
• The RNA
• The inserted gene (transgene)
• Any changes in the plant due to the insertion process

Viral Proteins and Susceptibility to Viral Infections

As described above, viruses produce proteins that attack and disable the plant cells‘ defenses, increasing the chances that the virus will thrive. More than 100 studies have shown, however, that the proteins created by one virus can promote infections by other related and unrelated viruses. ², ³

The viral proteins that function in plants may similarly disable viral defenses in humans, because important mechanisms that defend against viral attack are quite similar in plants and animals. Thus, consuming GM crops that make viral proteins in every cell may weaken our resistance to viruses.

This may be particularly true in the gut, where viral proteins would circulate after a meal -- and which is an important entry point for viral infections. Since we do not fully understand all the ways in which plant viruses overcome host defenses and we do not know which viral proteins are involved, we cannot identify in advance which viral transgenes are likely to be hazardous.

CLICK HERE to end the madness that is creating viral proteins that can stick in your gut and cause illness to you and your family.

Could Viral Proteins Be Toxic?

In addition to attacking viral defenses, viral proteins can also be toxic. They attack fundamental processes, such as the cycle by which a cell divides and the mechanism for creating proteins from RNA. ⁴ If these were damaged in human beings, it could have serious health consequences. Disrupting the cell cycle, for example, can lead to cancer.

Since these fundamental metabolic activities are similar in plants and humans, a toxic viral protein that attacks those processes in crops might similarly attack people. Viral proteins from one kingdom have in fact been shown to be toxic to organisms from other kingdoms. Plant viral proteins can affect yeast, for example, and some human viral proteins can disrupt plants. According to Latham, "There is no good reason why it should not happen the other way round."

In some cases, if a GM viral protein disrupts plant metabolism, it would be obvious to plant breeders and the variety would not be commercialized. But this would not always be the case.

Humans may be more sensitive than plants to the effects of the viral proteins. And, in some cases, the quantity of viral protein produced in a GM plant can be significantly increased. According to Latham, the proteins produced in GM crops have not been properly evaluated for toxicity in humans.

Hazardous RNA

According to Nature, RNA molecules are "now known to be vital in controlling many cellular processes in plants and animals." ⁴,⁵ In fact, "well over one-third of human genes appear to be" regulated by double stranded RNA (dsRNA).⁶ RNA also seems to be passed on to future generations -- a characteristic previously thought to be the exclusive domain of DNA. Studies indicate that RNA inherited from parents silenced a gene in mice⁷ and repaired an abnormal DNA sequence in a plant.⁸

According to the Centre for Integrated Research on Biosafety (INBI), "Once introduced into a model plant or animal, the effect of dsRNA is systemically spread throughout the organism and persists through the entire developmental period."⁹

Not only can RNA effects be transmitted through food, in many different organisms that effect can be inherited by the next generation (although this has not been demonstrated for humans).¹⁰ For example, when worms were fed bacteria engineered to produce dsRNA, the dsRNA survived the digestion in the worms‘ gut and penetrated into the gut cells and deeper tissues. It silenced the corresponding gene in the worm and in the offspring for at least two generations.¹¹

"The same dsRNA can have physiologically different effects at different concentrations, ¹²,¹³ and it is not always clear in advance which gene the dsRNA will impact.

Regulators have dismissed concerns that novel RNA sequences from GM crops may be hazardous. For example, when INBI raised the issue to Food Standards Australia New Zealand (FSANZ) in regard to a GM corn (that was not virus-resistant), FSANZ claimed that "RNA is rapidly degraded," and unlikely to survive digestion, enter human cells, or exert an effect.

INBI had to update FSANZ‘s obsolete argument. INBI pointed out that dsRNAs "are stable enough in mammalian cells to be routinely used as gene regulators." They cited recent studies demonstrating that dsRNA "is transmitted through food in other animals, where it survives degradation" and impacts gene expression. ¹⁴

For virus-resistant GM crops that are specifically engineered to create small regulatory dsRNA, regulators are similarly dismissive. They claim that people have eaten virus-infected food for a long time, so it must be safe.

This was the position of the US panel that looked at the GM plums. While their theoretical argument may sound strong, like many assumptions used as the basis for GM crop approvals, it lacks experimental verification. Given the significant potential for harm if the assumption is wrong, it is irresponsible not to test.

Even the argument on its own, however, is flawed. "In truth it is a half argument," says Latham. "The other half requires reliable evidence that people who ate the virus-infected crops were absolutely fine in every way." He says that "an experiment is only as good as its controls, but in this ‘experiment‘ there were none, because no one was found who hadn‘t eaten viruses."

How do you like being made a guinea pig in an experiment without controls? CLICK HERE to terminate your role as guinea pig.

If the natural RNA did turn out to be safe, the transgenic version might still be dangerous. The two versions of RNA are not identical and interchangeable. The naturally occurring sequence of a gene is usually altered by scientists prior to insertion.

In addition, the process of insertion can cause the gene to become truncated, mutated or littered with extraneous fragments. Other studies suggest that the transgene may rearrange spontaneously in subsequent growing seasons.¹⁵ A 2005 study also demonstrated that the transgenes in GM soybeans don‘t create RNA as they were designed to. The authors suggest that other GM crops may also produce unnatural, unintended RNA combinations. ¹⁶

According to geneticist Joe Cummins, "The fact that people may have eaten virus infected plums does not really indicate that the transgenic plum that resists virus infection in a novel way is safe for people." He says, "It is not unreasonable to suggest that a unique interfering plum RNA may be active in humans and animals."

Cummins says that "common sense requires adequate safety experiments," and he calls for "fuller testing of the small silencing RNA from the transgenic plum."¹⁷ INBI similarly cautions regulators against dismissing the risks of RNA based on unproven assumptions. They say that testing potential health impacts of RNA from GM crops on humans, which has not been done for any GM crops thus far, is "imperative."¹⁸

Consequences of Shifting RNA Viruses to DNA

Until the introduction of virus-resistant GM crops, target viruses existed exclusively as RNA-based organisms. When scientists create a viral transgene, however, they introduce an entirely new DNA version. According to Latham, this carries a generally unacknowledged potential risk. "The virus is available for recombination with a totally new spectrum of organisms," he warns. "The danger would become especially important if the transgenic protein were useful to the organism that picked it up."

Consider, for example, the possibility that viral transgenes might transfer into the DNA of gut microorganisms.

This type of "horizontal gene transfer" from GM food to gut bacteria was confirmed in the case of Roundup Ready soybeans. That was the only human feeding study ever conducted on GM food.

No such test has been carried out using virus-resistant crops, but transfer of viral transgenes is certainly plausible. Once transferred, our own bacteria may produce viral proteins inside our intestines over the long term, potentially weakening our defenses against viral infection and attacking fundamental metabolic processes.

[Note: During the development of the GM plum, the same viral transgene was inserted into many different plum cells. Although GM plums created from these other experimental insertions produced viral protein, the transgenic plum under review by the USDA, "Honey Sweet," produces little or no viral protein. While this reduces risks somewhat, if the viral RNA transfers into other viruses or the viral DNA ends up in gut bacteria, they could produce potentially harmful viral protein in that new organism. This needs to be studied.]

Creation of New Harmful Plant Viruses

In addition to posing risks for humans, virus-resistant GM crops may increase the likelihood for new viruses to attack the plant. This could occur via the action of viral proteins. Proteins produced from one virus may attack the host cells‘ defenses, making it more susceptible to other viruses. In one study, proteins from viral transgenes allowed a plant to become infected with an insect virus not normally found in plants.¹⁹

One type of protein produced by viruses is called a coat protein. It surrounds (encapsulates) the RNA, protecting it from being broken down by threats like ultra violet light or enzymes.

It is possible for a coat protein from one virus to encapsulate another virus. This makes it possible for the new virus to be picked up by an insect and transported to other plants. The risk of encapsulating the wrong virus (transcapsulation) is not a unique risk of GM plants, but the presence of coat protein produced in every cell of the plant can increase the probability that it will occur.

Another concern about GM crops is that inserted viral genes can come into proximity with related or unrelated natural viruses and recombine to create new versions. These new "offspring" viruses can be quite different from either "parent."

Many reports specifically demonstrate that natural viruses do recombine with the viral sequences inserted into GM plants,²⁰ including the viral transgene used in plums.²¹ "In some cases recombination occurred at very high rates in up to 80 percent²² of all plants tested."²³ According to Latham, experiments suggest that recombination between viral transgenes in the currently commercialized GM crops and naturally occurring viruses are inevitable. The consequences of the recombination, however, are unpredictable.

Of particular concern is that viral genes can transfer to viruses not normally infecting the plant.²⁴ The invading virus, not adapted to that plant, would acquire a transgene that is adapted, making it more likely to attack that plant.²⁵ It is ironic that GM crops designed to resist one virus "may be especially susceptible to new infectious viral diseases."²⁶

Diseased plants may impact human health.

If GM plants do generate new plant viruses, there are some implications for human health:

• The infected plants create viral proteins. As discussed, these may increase our susceptibility to viral infection or be toxic.

• If plants develop novel viruses, it is likely that they will be treated with pesticides, which increases human health risks.

• Plants infected by viruses may have altered levels of anti-nutrients, toxins, and allergens, and may be more susceptible to mold infestation, all of which may affect consumer health.

It is important to note that the key concern about creating new viruses is related to plant viruses, not human viruses. Natural barriers tend to block a virus in one kingdom from attacking organisms in another kingdom. Therefore, the tendency to create new viruses in plants does not mean that they will attack humans.

On the other hand, when genes from two distinct viruses were inserted separately into a plant, the two viral proteins made the plant susceptible to infection by an animal (insect) virus. There are also other examples of cross kingdom viral adaptations.²⁷ So in theory, the use of transgenic viral genes may increase the probability that a plant can carry a virus that will function in humans. With little or no research on this, the risk remains speculative.

Generic Risks from GM Plants

While most of the concerns raised thus far relate to disease-resistant GM crops, all GM varieties carry generic risks.

The process of creating a GM crop typically causes significant mutations and altered gene expressions throughout the genome, with the possible creation of toxins, allergens, carcinogens, and anti-nutrients. The transgene may rearrange during insertion or perhaps at a later time, producing proteins that were never intended or tested. All these uncontrolled and unpredicted changes within the DNA provide opportunities for RNA sequence creation with negative impacts. According to INBI, the potential for gene insertion to create regulatory RNA "is too high by chance to ignore."²⁸

Additionally, genetic material inserted with the transgene-the promoter, antibiotic resistant marker and terminator-all carry significant risks that have not been properly studied. And many of the safety-related assumptions initially proclaimed by the biotech industry about these elements were overturned since.

Responding to the Threat

The FDA has no required safety studies for GM crops and the USDA continues to quote outdated theories (see side bar below for some examples). These actions are consistent, however, with the fact that US regulatory agencies are officially charged with the responsibility to promote the biotechnology industry.

CLICK HERE if you want to stop your tax dollars from being used to pump up the biotech industry.

Originally, politicians claimed this effort would increase US exports. Now with worldwide rejection of GM crops actually shrinking US corn and soy exports to the point of requiring an extra $2-3 billion per year in price supports, promotion of biotech appears to be more about appeasing a powerful corporate lobby.

Consumers‘ concerns about GM foods are not always heeded by governments; however, the food industry is more responsive. Their concern about potential loss of markets has a significant impact in reigning in biotech expansion.

• When Monsanto tried to introduce their GM wheat, an Iowa State University economist projected a loss of 30-50 percent of the US foreign wheat sales and drop in prices by about a third.²⁹ The wheat industry lobbied hard for North America to be a GM-wheat-free-zone and Monsanto withdrew its application.³⁰

• When Hawaii coffee growers realized that GM coffee might destroy its premium market, it successfully appealed to the University of Hawaii not to develop any GM varieties.

• GM flax was taken off the market in 2001 due to pressure from the Flax Council of Canada and the Saskatchewan Flax Development Commission.³¹

• GM sugar beets were rejected by US sugar refiners.³²

• Warnings from rice millers and others halted the commercialization of GM rice.³³

Now it‘s time for the plum producers to protect their markets. The US is the third leading plum exporter. California grows the vast majority, with more than $130 million worth grown in 2002. The plum pox virus, which had infected trees in Pennsylvania, is not even a West Coast phenomenon. But if GM plums are introduced anywhere in the US, market rejection will surely be an issue, along with contamination, rejected shipments, and extra costs for segregation and testing.

If you wish to give friendly encouragement to the plum and prune industry to ask for the USDA to stop the GM plum, please go to www.responsibletechnology.org. In this case, it won‘t require that Monsanto or another biotech company withdraw their application. The GM plums were developed and promoted by the USDA itself.

As for other virus-resistant crops, Hawaiian GM papayas are shipped to Canada and a few cities on the West Coast, such as Los Angeles and San Francisco. To avoid it in those locations, inquire about the source of the fruit (and recommend to vendors to avoid it as well.)

Unfortunately, organic and non-GM conventional papaya from Hawaii are easily contaminated by GM varieties. Cross-pollination of a non-GM papaya tree can make the seeds GM, while the flesh of the fruit remains non-GM. Consequently, some organic growers planted the seeds of "organic" papaya, only to discover that their orchard was entirely GM. Similarly, those buying papaya at the market may throw the seeds on the ground or plant them in their garden, inadvertently spreading the GM variety.

In a study in 2004, "nearly 20,000 papaya seeds from across the Big Island, 80% of which came from organic farms and the rest from backyard gardens or wild trees, showed a GM contamination level of 50%."³⁴ The GM plum under review can likewise turn the seeds of neighboring trees into GM varieties.

The virus-resistant GM zucchini and crookneck squash varieties are mixed in low quantities with conventional brands in the US. To avoid them, it may be easiest to buy organic, which has probably suffered minimal contamination. As for the four major GM crops, soy, corn, cottonseed and canola, go to www.seedsofdeception.com and discover how to avoid them when shopping or in restaurants.

Safe eating!

CLICK HERE to voice your opinion to the plum industry and urge them to pull these toxic foods off the market.

CLICK HERE to help encourage more safety studies before bringing new GM plants onto the market.

Jeffrey Smith is the author of the international bestseller, Seeds of Deception. The information in this article presents some of the numerous health risks of GM foods that will be presented in his forthcoming book, Genetic Roulette: The documented health risks of genetically engineered foods, due out in the fall.

Spilling the Beans is a monthly column available at www.responsibletechnology.org.

Permission is granted to publishers and webmasters to reproduce issues of Spilling the Beans in whole or in part. Just email us at column@seedsofdeception.com to let us know who you are and what your circulation is, so we can keep track.

The Institute for Responsible Technology is working to end the genetic engineering of our food supply and the outdoor release of GM crops. We warmly welcome your donations and support.

Click here if you‘d like to make a tax-deductible donation, or click here if you would like to become a member of the Institute for Responsible Technology. Membership to the Institute for Responsible Technology costs $25 per year. New members receive The GMO Trilogy, a three-disc set produced by Jeffrey Smith (see www.GMOTrilogy.com)

This article used as its primary source, the following article, combined with personal communication with Dr. Jonathan Latham. Jonathan R Latham, PhD and Ricarda A Steinbrecher, PhD, Horizontal gene transfer of viral inserts from GM plants to Viruses, GM Science Review Meeting of the Royal Society of Edinburgh on "GM Gene Flow: Scale and Consequences for Agriculture and the Environment" 27 January 2003 -- amended February 2004 www.econexus.info/pdf/Horizontal-Genes-virus-2004.pdf

1 http://www.greenpeace.org/raw/content/international/press/reports/FailureGEPapayainHawaii.pdf

2 Comments on GM Science Review, From Econexus, the Five Year Freeze, Friends of the Earth, GeneWatch UK, Greenpeace, the Soil Association, and Dr Michael Antoniou, October 14th 2003

3 Nearly every type of virus protein has this ability: viral coat proteins (A),, viral movement proteins (B); viral replicase proteins (C); viral proteins involved in overcoming host defenses(D) and miscellaneous viral proteins(E). (A) E.g Taliansky, M. E., and Garcia-Arenal, F. (1995). Role of cucumovirus capsid protein in long-distance movement within the infected plant. J Virol 69(2), 916-22; Briddon, R. W., Pinner, M. S., Stanley, J., and Markham, P. G. (1990). Geminivirus coat protein gene replacement alters insect specificity. Virology 177(1), 85-94; (B) E.g Cooper, B., et al. (1995). A defective movement protein of TMV in transgenic plants confers resistance to multiple viruses whereas the functional analog increases susceptibility. Virology 206(1), 307-13; Ziegler-Graff, V., Guilford, P. J., and Baulcombe, D. C. (1991). Tobacco rattle virus RNA-1 29K gene product potentiates viral movement and also affects symptom induction in tobacco. Virology 182(1), 145-55; (C) Siegel, R. W., Adkins, S., and Kao, C. C. (1997). Sequence-specific recognition of a subgenomic RNA promoter by a viral RNA polymerase. Proc Natl Acad Sci U S A 94(21), 11238-43; Teycheney, P. Y., et al. (2000). Synthesis of (-)-strand RNA from the 3‘ untranslated region of plant viral genomes expressed in transgenic plants upon infection with related viruses. J Gen Virol 81(4), 1121-6; (D) Pruss, G., et al (1997). Plant viral synergism: the potyviral genome encodes a broad-range pathogenicity enhancer that transactivates replication of heterologous viruses. Plant Cell 9(6), 859-68; Sonoda, S., et al. (2000). The helper component-proteinase of sweet potato feathery mottle virus facilitates systemic spread of potato virus X in Ipomoea nil. Phytopathology 90, 944-950; and (E) Agranovsky, A.A. et al. (1998). Beet yellows closterovirus HSP70-like protein mediates the cell-to-cell movement of a potexvirus transport-deficient mutant and a hordeivirus-based chimeric virus. J Gen Virol 79 ( Pt 4), 889-95; Sunter, G., Sunter, J. L., and Bisaro, D. M. (2001). Plants expressing tomato golden mosaic virus AL2 or beet curly top virus L2 transgenes show enhanced susceptibility to infection by DNA and RNA viruses. Virology 285(1), 59-70.

4 Hao et al 2003 The plant cell 15 1034-1048; Kong et al 2000 EMBO journal 19 3485-3495; Rubino et al 2000 Journal of General Virology 81 279-286; Dalmay et al 2001 EMBO Journal 20 2069-2077

5 Helen Pearson, What is a Gene?, Nature, Vol 441, May 25, 2006

6 Lewis, B. P., Burge, C. B. and Bartel, D. P. (2005). Conserved seed pairing, often flanked by adenosines, indicates that thousands of human genes are microRNA targets. Cell 120, 15-20.

7 Minoo Rassoulzadegan et al, RNA-mediated non-mendelian inheritance of an epigenetic change in the mouse, Nature 441, 469-474, May 25, 2006

8 Lolle, S. J., Victor, J. L., Young, J. M. & Pruitt. R. E. Genome-wide non-mendelian inheritance of extra-genomic information in Arabidopsis, Nature 434, 505-509 (2005).

9 Cretenet, M., Goven, J., Heinemann, J.A., Moore, B. and Rodriguez-Beltran, C. 2006. Submission on the DAR for Application A549 Food Derived from High-Lysine Corm LY038: to permit the use in food of high-lysine corn. www.inbi.canterbury.ac.nz.

10 Cogoni, C. and G. Macino (2000). "Post-transcriptional gene silencing across kingdoms." Curr. Opin. Genet. Develop. 10: 638-643; and Timmons, L., D. L. Court, et al. (2001). "Ingestion of bacterially expressed dsRNAs can produce specific and potent genetic interference in Caenorhabditis elegans." Gene 263: 103-112.

11 Timmons, L., D. L. Court, et al. (2001). "Ingestion of bacterially expressed dsRNAs can produce specific and potent genetic interference in Caenorhabditis elegans." Gene 263: 103-112.

12 Zhao, Z., Y. Cao, et al. (2001). "Double-Stranded RNA Injection Produces Nonspecific Defects in Zebrafish." Develop. Biol. 229: 215-223.

13 Jack Heinemann et al, Submission on Application A549 Food Derived from High Lysine Corn LY038: to permit the use in food of high lysine corn, Submitted to Food Standards Australia/New Zealand (FSANZ) by New Zealand Institute of Gene Ecology, January 22, 2005.

14 Cretenet, M., Goven, J., Heinemann, J.A., Moore, B. and Rodriguez-Beltran, C. 2006. Submission on the DAR for Application A549 Food Derived from High-Lysine Corm LY038: to permit the use in food of high-lysine corn. www.inbi.canterbury.ac.nz.

15 Collonier C, Berthier G, Boyer F, Duplan M-N, Fernandez S, Kebdani N, Kobilinsky A, Romanuk M, Bertheau Y. Characterization of commercial GMO inserts: a source of useful material to study genome fluidity. Poster presented at ICPMB: International Congress for Plant Molecular Biology (n°VII), Barcelona, 23-28th June 2003. Poster courtesy of Dr. Gilles-Eric Seralini, Président du Conseil Scientifique du CRII-GEN, www.crii-gen.org; also "Transgenic lines proven unstable" by Mae-Wan Ho, ISIS Report, 23 October 2003

16 Andreas Rang et al, Detection of RNA variants transcribed from the transgene in Roundup Ready soybean Eur Food Res Technol (2005) 220:438-443.

17 Joe Cummins, Transgenic virus resistant plums, June 11, 2006

18 Jack Heinemann et al, Submission on Application A549 Food Derived from High Lysine Corn LY038: to permit the use in food of high lysine corn, Submitted to Food Standards Australia/New Zealand (FSANZ) by New Zealand Institute of Gene Ecology, January 22, 2005.

19 Dasgupta, R., Garcia, B. H., 2nd, and Goodman, R. M. (2001). Systemic spread of an RNA insect virus in plants expressing plant viral movement protein genes. Proc Natl Acad Sci U S A 98(9), 4910-5.

20 Jonathan R Latham, PhD and Ricarda A Steinbrecher, PhD, Horizontal gene transfer of viral inserts from GM plants to Viruses, GM Science Review Meeting of the Royal Society of Edinburgh on "GM Gene Flow: Scale and Consequences for Agriculture and the Environment" 27 January 2003 -- amended February 2004

21 Mark, Varrelmann et al, Transgenic or Plant Expression Vector-Mediated Recombination of Plum Pox Virus, JOURNAL OF VIROLOGY, Aug. 2000, p. 7462-7469 Vol. 74, No. 16

22 Borja M, Rubio T, Scholthof HB, et al. (1999) Restoration of wild-type virus by double recombination of tombusvirus mutants with a host transgene. MPMI 12: 153-162 1999

23 Jonathan R Latham, PhD and Ricarda A Steinbrecher, PhD, Horizontal gene transfer of viral inserts from GM plants to Viruses, GM Science Review Meeting of the Royal Society of Edinburgh on "GM Gene Flow: Scale and Consequences for Agriculture and the Environment" 27 January 2003 -- amended February 2004

24 Gibbs M (1994) Risks in using transgenic plants? Science 264: 1650-1651

25 Weiland I and Edwards M (1996) A single nucleotide substitution in the alpha a gene confers oat pathogenicity to barley stripe mosaic virus strain ND18. MPMl9: 62-67

26 Comments on GM Science Review, From Econexus, the Five Year Freeze, Friends of the Earth, GeneWatch UK, Greenpeace, the Soil Association, and Dr Michael Antoniou, October 14th 2003

27 In Gibbs, et al, 1999 PNAS 99 8022-27, there is a report of a hypbrid vertebrate/plant virus that infects plants. In De Medeiros, et al., 2005 PNAS 2005 vol 102 1175-80, Also available is de medeiros et al 2005 PNAS 2005 vol 102 1175-80, a gene from an insect was expressed in human cell lines, and allowed the cells to become infected by a plant virus (tomato spotted wilt virus).

28 Jack Heinemann et al, Submission on Application A549 Food Derived from High Lysine Corn LY038: to permit the use in food of high lysine corn, Submitted to Food Standards Australia/New Zealand (FSANZ) by New Zealand Institute of Gene Ecology, January 22, 2005.

29 Robert Wisner, Genetically Modified Wheat is Still a Market Risk, WORC May 2005 www.worc.org/pdfs/wisnersummary-05-05.pdf

30 Washington Post (May 11, 2004). Monsanto Pulls Plan To Commercialize Gene-Altered Wheat, http://www.washingtonpost.com/wp-dyn/articles/A15998-2004May10.html

31 According to the Canadian Food Inspection Agency, Plant Biosafety Office, the GE flax was deregistered on April 1, 2001; The Leader Post (June 22, 2001) GM flax off the market

32Wall Street Journal (April 27, 2001) Refiners shun bioengineered sugar beets, frustrating plans for Monsanto, Aventis, http://www.biotech-info.net/refiners_shun.html

33 Schubert R. (Feb. 22, 2002) GE rice resistance -- market rejects gene-altered crop, http://www.cropchoice.com/leadstry0137.html?recid=595

34 New Research Reveals Widespread GMO Contamination and Threats to Local Agriculture From the World‘s First Commercially Planted Genetically Engineered Tree, Press release, GMO-Free Kauai, September 9 2004

35 Jonathan R Latham, PhD and Ricarda A Steinbrecher, PhD, Horizontal gene transfer of viral inserts from GM plants to Viruses, GM Science Review Meeting of the Royal Society of Edinburgh on "GM Gene Flow: Scale and Consequences for Agriculture and the Environment" 27 January 2003 -- amended February 2004

36 De Zoeten GA (1991). Risk assessment: Do we let history repeat itself? Phytopathology 81: 585-86; Hull, R. (1994). Risks in using transgenic plants? Science 264, 1649-50; author reply 1651-2; Gibbs M (1994) Risks in using transgenic plants? Science 264:1650-1651; UCS 1994; Allison, R. F., Greene, A., and Schneider, W. L. (1997). Significance of RNA recombination in capsid protein-mediated virus-resistant transgenic plants. In "Virus-resistant transgenic plants: potential ecological impact" (M. Tepfer, and E. Balazs, Eds.). INRA and Springer-Verlag, Versailles/Heidelberg; and Gibbs, M., Armstrong, J., Weiller, E., and Gibbs, A. (1997). Virus evolution; the past, a window on the future? In "Virus-resistant transgenic plants: potential ecological impact" (M. Tepfer, and E. Balazs, Eds.), pp. 1-19. INRA and Springer-Verlag, Versailles/Heidelberg.

37 Falk BW, and Bruening G (1994) Will transgenic crops generate new viruses and new diseases. Science 263: 1395-1396, USDA (1994) Docket No. 92-127-4 Environmental Assessment and finding of no significant impact for ZW-20 squash, J. Hammond et al, (1999) Epidemiological risks from mixed virus infections and transgenic plants expressing viral genes. Adv. Virus Res. 54: 189-314.

38 Barker H (1989) Specificity of effect of sap-transmissible viruses in increasing the accumulation of luteoviruses in co-infected cells. Ann. Appl. Biol. 115: 71-78, and Latham JR et al (1997) Induction of plant cell division by beet curly top virus gene C4. Plant J. 11: 1273-1283

39 e.g., Simon, K. O., Cardamone, J. J., Jr., Whitaker-Dowling, P. A., Youngner, J. S., and Widnell, C. C. (1990). C

40 Falk BW, and Bruening G (1994) Will transgenic crops generate new viruses and new diseases. Science 263: 1395-1396; USDA (1994) Docket No. 92-127-4 Environmental Assessment and finding of no significant impact for ZW-20 squash; and Rubio T; Borja M; Scholthof HB; Jackson AO (1999) Recombination with host transgenes and effects on virus evolution: An overview and opinion. MPMI 12: 87-92

41 Schwartz M et al (2002) A positive strand RNA virus replication complex parallels form and function of retrovirus capsids. Mol. Cell 9: 505-514

42 Tepfer M (2002) Risk assessment of virus-resistant transgenic plants. Ann. Rev. Phytopathol, 40: 467

43 Kasschau K and Carrington JC (1998) A counterdefensive strategy of plant viruses: suppression of post transcriptional gene silencing. Cell 95: 461-470; and Tepfer M (2002) Risk assessment of virus-resistant transgenic plants. Ann. Rev. Phytopathol, 40: 467

44 Falk BW, and Bruening G (1994) Will transgenic crops generate new viruses and new diseases. Science 263: 1395-1396; AIBS 1995, Beltsville, Maryland; Aaziz R, Tepfer M (1999) Recombination in RNA viruses and in virus-resistant transgenic plants. J Gen Virol 80: 1339-1346 Part 6 JUN 1999; T. Rubio et al, (1999) Recombination with host transgenes and effects on virus evolution: An overview and opinion. MPMI 12: 87-92; and J. Hammond et al, (1999) Epidemiological risks from mixed virus infections and transgenic plants expressing viral genes. Adv. Virus Res. 54: 189-314

45 Falk BW, and Bruening G (1994) Will transgenic crops generate new viruses and new diseases. Science 263: 1395-1396; J. Hammond et al, (1999) Epidemiological risks from mixed virus infections and transgenic plants expressing viral genes. Adv. Virus Res. 54: 189-314; T. Rubio et al, (1999) Recombination with host transgenes and effects on virus evolution: An overview and opinion. MPMI 12: 87-92

46 For example Briddon R et al (1996) Analysis of the nucleotide sequence of the treehopper-transmitted geminivirus, Tomato pseudo-curly top virus, suggests a recombinant origin. Virology 219: 387-394; Zhou et al (1997) Evidence that the DNA-A of a geminivirus associated with severe cassava mosaic virus disease in Uganda has arisen by interspecific recombination. J. Gen Virol. 78: 2101-2111; Moonan F et al (2000) Sugarcane yellow leaf luteovirus: An emerging virus that has evloved by recombination between luteoviral and poleroviral ancestors. Virology 269: 156-171

47 Anderson et al (1992) Characterisation of a cauliflower mosaic virus isolate that is more severe and accumulates to higher concentrations than either of the strains from which it was derived. MPMI 5: 48-54; Ding S et al (1996) An interspecific hybrid RNA virus is significantly more virulent than either parental virus. PNAS 93: 7470-7474; Fernandez-cuartero B et al. (1994) Increase in the relative fitness of a plant virus RNA associated with its recombinant nature. Virology 203: 373-377

48 USDA (1994) Docket No. 92-127-4 Environmental Assessment and finding of no significant impact for ZW-20 squash

49 For example, Voinnet O et al. (1999). Suppression of gene silencing: a general strategy used by diverse DNA and RNA viruses of plants. Proc. Natl. Acad. Sci. USA 96: 14147-52

50 Falk BW, and Bruening G (1994) Will transgenic crops generate new viruses and new diseases. Science 263: 1395-1396; T. Rubio et al, (1999) Recombination with host transgenes and effects on virus evolution: An overview and opinion. MPMI 12: 87-92

© Copyright 2006 by Jeffrey M. Smith.